1. Field of the Invention
The invention pertains to heat converters used with geothermal wells wherein the heat converter includes portions in direct contact with the hot underground medium, such as brine, and a heat exchanger portion associated with the converter converts water deposited upon the converter to steam.
2. Description of Related Art
In the desire to convert geothermal energy to steam or hot water so as to utilize such energy for practical purposes, such as the generation of electricity, geothermal wells are drilled in those regions wherein high temperature brine, water, steam, or molten rock may be available. Attempts to directly utilize geothermal steam in turbines for electric generation purposes have largely been unacceptable due to contaminants within the steam corroding the electrical generation apparatus. Accordingly, it has become more practical to convert the geothermal heat to a closed loop steam circuit wherein the steam may be maintained free of contaminants, such as shown in U.S. Pat. Nos. 3,862,545; 4,057,964; and 4,272,961.
However, existing energy conversion systems for converting geothermal heat to usable steam have high maintenance costs due to the corrosion of the heat converter used in the system which is in direct engagement with the hot subterranean medium. Geothermal brine, for instance, usually contains a number of chemicals and compositions highly corrosive to conventional heat converter materials.